Born into poverty in Wales, Pryce Lewis emigrated to the USA in search of a better life – and became embroil in a daring and dangerous underworld of life as a Civil War spy.

Tales of daring, secret missions behind enemy-lines, fake identities and fighting for the sanctity of the United States of America sound like plotlines from a Hollywood blockbuster – not the escapades of a 19th century Welsh flannel-weaver.

But Pryce Lewis was no ordinary flannel-weaver.

Born into a life of poverty in Newtown, Powys, in 1832, Lewis could never have imagined the life of Civil War espionage that awaited him across the Atlantic.

Having travelled to the US in 1856 in search of a better quality of life, by 1859 his itchy feet had led him to Chicago where he joined a detective agency belonging to Allan Pinkerton

Two years later, the American Civil War broke out, with the Union states of the north and the Confederate states of the south battling over the contentious issue of slavery.

With the nation at war, Lewis became embroiled in infiltrating the Southern forces to gather intelligence.

Lewis’ information surrounding the town of Charleston and what the Confederates’ position there, was vital. Disguised as an English aristocrat, he befriended colonels and put his life on the line to get information across the battle-lines. At one point the Welshman was even captured, in the town of Richmond, Virginia but promptly escaped from Henrico County Jail along with eight others.

Shortly after this escape Lewis and the others were and the Welshman was sentenced to be hanged.

Ultimately he escaped the punishment because he was a British citizen.

After the war ended he became a bailiff and detective at the Old Capitol Prison, but he never settled in any job and died virtually destitute.

Gavin Mortimer has documented the life of Pryce Lewis in his book Double Death: the True Story of Pryce Lewis, The Civil War’s Most Daring Spy.

"Arguably Lewis provided the Union cause with its most valuable piece of intelligence during the war, enabling the Northern army to push through West Virginia and strike a blow that, while strategically wasn’t massive, gave the North a crucial propaganda victory at a time when the war hadn’t been going well," he said.

"It’s an insult to Lewis that his contribution in defeating the South has been overlooked, in the US as in Britain

"Perhaps he lacked the glamour, the intrigue, and the fact he was a man might have worked against him.

"Female spies were all the rage in the Civil War.

"His greatest coup was to disguise himself as an English aristocrat and travel round the south, gathering intelligence.

"He was an extraordinary man, and spy, one who has been criminally neglected by history.

"Wales should be made more aware of his role in the Civil War – and the fact he refused until his dying day to become a US citizen because of his pride in his heritage."

Despite his heroics Lewis committed suicide in New York in 1911 by throwing himself off the top of the Pulitzer Building in New York after spending his post-war years practically destitute after being refused a pension as he was still a British citizen.

David Pugh, chair of the Newtown Civic Society, has carried out extensive research into Lewis’ life, and aided Mr Mortimer’s book.

"He was a remarkable man," said Mr Pugh.

"It seems to be a Welsh tradition to go somewhere else and do great things.

"The house he was born in, in Newtown is now called Lewis House and should have a blue plaque in it in my opinion."

But despite the colourful nature of Lewis’ life, his remarkable tale may have been lost to history had it not been for the work of one Harriet Shoen – a friend of Lewis’s only child with his wife Maria, Mary – who carried out extensive research into his life.

Those studies were then donated anonymously to the History Society of St Lawrence County, New York, after Ms Shoen’s death in 1967.

The Pryce Lewis Collection is housed at the St Lawrence University Library, and where found by Mr Mortimer as he researched a separate book about the Civil War.

"When I was researching another book I saw a report on Lewis’s suicide in 1911," he said.

"I knew at once there was a great story there."

Conversely, Mr Pugh discovered the story of Pryce Lewis while examining old newspaper clippings around 20 years ago.

"I came across the press reports of his death," he said.

"Someone from America had sent a clipping about his death to the Montgomeryshire Express and they printed it."

Mr Pugh also discovered how many people from Newtown emigrated to America during the 19th Century, settling on the East Coast, including Massachusetts.

"I went to a cemetery on a visit to North Adams and it was as if I was walking through a cemetery in Newtown. The names were all Newtown names."

Professor Jerry Hunter has done a great deal of research into the Welsh-speaking community’s role in 19th century America as part of his remit as a Professor at the School of Welsh at Bangor University.

He explained that although most Welsh-speaking communities were in the northern states, there were Americans of Welsh heritage fighting on both sides during the Civil War.

He said: "It’s no surprise that most Welsh-speaking Civil War soldiers were in the Union/Northern army.

"But their contribution, if not large in terms of numbers, was very interesting and significant for a number of reasons.

"It seems that comparatively large numbers of Welsh-speaking American men joined the Union army compared to the size of their communities."

The Professor, who is originally from Ohio, said Lewis had made a "significant contribution" to a number of military campaigns during his career as a spy.

"Lewis went to Tennessee and Virginia during the war, apparently helped by pro-Union southerners in those areas, and gathered information for the Union army about the Confederate military," he said.

"In his first wartime assignment, Lewis was sent to Tennessee to gather intelligence for the Union armies.

"This state had been the last to leave the Union.

"Both sides fought fiercely to control it because of its strategic importance.

"General George McClellan was most impressed with the reports Lewis provided on the Confederate army and its movements.

"I am not a military historian, but from what I understand, this information made a significant contribution to several military campaigns."

As well as Pryce Lewis, Professor Hunter points out that there were other important Welsh Americans involved in the campaign.

He added: "Another interesting Welsh-American was Isaac Cheshire.

"He worked in the Department of the Interior in President Abraham Lincoln’s government during the war, and wrote lengthy, and often fiery, political editorials supporting the war effort and Lincoln for Y Drych.

"There was also Colonel William H. Powell. Like many of his soldiers, he lived in Ohio before the war, but he led 2nd West Virginia Cavalry, a Union regiment, and played a large role in the guerrilla fighting in the mountains, helping to curb Confederate Raiders like Mosby.

"I’d also single out the Reverend Erasmus Jones, chaplain with the 21st United States Colored Infantry, a regiment comprised mostly of freed slaves.

"Rev Jones gave tribute in print to these men’s efforts to free other slaves, and he helped prepare the former slaves for their new lives as free men by helping to teach them to read and write."

Many Welsh-Americans before and during the Civil War actively opposed slavery, with Professor Hunter revealing that by the start of the war in 1861 the intellectual, moral and religious leaders of Welsh-speaking America were united in their opposition to it.

He added: "The Welsh-American press tended to portray the war at least in part as a war against slavery, and, based on a study of the great number of letters (and a few diaries) by Welsh-speaking Union soldiers which have survived, it seems that this ideological interpretation of the war was embraced by many common Welsh-American soldiers. More so than among other ethnic groups in the Union army, it would seem."

"The Reverend Robert Everett, a Congregationalist minister in Oneida County, New York, editor and publisher of the journal ‘Y Cenhadwr Americanaidd.’

". He did more than any other single person to radicalise Welsh America and list Welsh-speaking Americans in the struggle against slavery.

"Even though he was – or had been – a pacifist, when the war started he decided to turn his back on his pacifism and support the Union war effort, because he saw it as a war against slavery."

The involvement of Welsh Americans and Welsh immigrants in the Civil War is as colourful as the story of the war itself.

Men such as Pryce Lewis ensured the passion and tenacity of the nation spread across the globe – whilst selflessly risking their own lives.

Double Death: the True Story of Pryce Lewis, The Civil War’s Most Daring Spy, by Gavin Mortimer, is published by Walker & Company, priced $26

Next page: Other Welsh Civil War heroes

It wasn’t just Pryce Lewis who made his mark on the American Civil War. Many Welsh Americans took part in armed combat and came away with military medals for their efforts.

Joseph Davies, born 1838 in Llangynidr near Brecon, enlisted into the Ohio Infantry.

A blacksmith by trade, he was awarded the Congressional Medal of Honour for extraordinary heroism in action at Franklin, Tennessee for capture of the Confederate flag.

David Edwards, born in Wales in 1841, entered into service in 1863.

A Private in the 146th New York Infantry (Garrard’s Tigers) he won his Congressional Medal of Honour in 1865 a year after being promoted to corporal.

He captured the enemy flag at Five Forks in Virginia.

He was a farmer.

John Griffiths was born in 1835 in Cardiff was petty officer in the US Navy and sailed on the USS Santiago De Cuba.

He won his medal during the landing and attack on Fort Fisher in January 1865. He only served one year in the navy and was discharged on June 17 1865.

Thomas Davies from Haverfordwest was a private in the 2nd New York Heavy Artillery and was wounded in action at Cold Harbour, Virginia.

He won his Congressional Medal of Honour in 1865.

William Henry Powell, a Pontypool-born President of Belleville Nailworks in Illinois, was awarded a Congressional Medal of Honour for distinguished service at a raid at Sinking Creek, Virginia.

The Captain of the 2nd West Virginia Cavalry charged an captured a 500-strong enemy camp with just 20 men, none of whom lost their lives.

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